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UDP broadcast on layer 3 switch

A user has several VLAN in a development/test environment. The routing switch is a Catalyst 3550.

Currently a handfull of UDP port are broadcast between VLAN. The user would like all UDP port to be broadcast.

I did explained why it is not a good idea but I would like to know if it is possible at all.

Does the IP FORWARD-PROTOCOL command allow all ports??

Is it possible to specify a range of UDP port??



Re: UDP broadcast on layer 3 switch

Enabling a helper address or UDP flooding on an interface causes the Cisco IOS software to forward particular broadcast packets. You can use the ip forward-protocol command to specify exactly which types of broadcast packets you would like to have forwarded. A number of commonly forwarded applications are enabled by default. Enabling forwarding for some ports (for example, Routing Information Protocol (RIP) may be hazardous to your network.

If you use the ip forward-protocol command, specifying only UDP without the port enables forwarding and flooding on the default ports.

other than that, its per port....